Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Quem eram os filhos de Benjamin Harrison?
 ###Tabelas: CREATE TABLE workplace_killings (workplace_killings_id AUTO_INCREMENT PRIMARY KEY, Perpetrator VARCHAR, Date VARCHAR, Year INT, Location VARCHAR, Country VARCHAR, Killed INT, Injured VARCHAR) CREATE TABLE list_of_the_most_populous_us_counties_sorted_according_to_the_mid-2011_official_estimate_by_the_uscb (list_of_the_most_populous_us_counties_sorted_according_to_the_mid-2011_official_estimate_by_the_uscb_id AUTO_INCREMENT PRIMARY KEY, Rank VARCHAR, County VARCHAR, State VARCHAR, Land area (km²) VARCHAR, Land area (mi²) VARCHAR, April 1, 2010 census VARCHAR, April 1, 2010 density (/km²) VARCHAR, April 1, 2010 density (/mi²) VARCHAR, July 1, 2010 official estimate VARCHAR, July 1, 2010 density (/km²) VARCHAR, July 1, 2010 density (/mi²) VARCHAR, July 1, 2011 official estimate VARCHAR, July 1, 2011 density (/km²) VARCHAR, July 1, 2011 density (/mi²) VARCHAR, Mid-2010 to mid-2011 change (Absolute) VARCHAR, Mid-2010 to mid-2011 change (%) VARCHAR, County seat or courthouse VARCHAR) CREATE TABLE u.s._presidents (u.s._presidents_id AUTO_INCREMENT PRIMARY KEY, Name VARCHAR, Deceased Spouse VARCHAR, Cause of Death VARCHAR, Date of Spouses Death VARCHAR, Length of Marriage VARCHAR, Children Together VARCHAR, Current Marital Status VARCHAR) CREATE TABLE sporting_events (sporting_events_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Nation VARCHAR, Gold INT, Silver INT, Bronze INT, Total INT) CREATE TABLE regions (regions_id AUTO_INCREMENT PRIMARY KEY, In English VARCHAR, In Finnish VARCHAR, In Swedish VARCHAR, Capital VARCHAR, Regional state administrative agency VARCHAR)  
SELECT Children Together FROM u.s._presidents WHERE Name = Benjamin Harrison